Method of making end caps for pipe railings



Aug. 28, 1962 A. A. WAGNER 3,050,844

METHOD OF MAKING END CAPS FOR PIPE RAILINGS Original Filed Sept. 5, 1957 INVENTOR. Amp/l H. [Mas/veg BY ATTORNEY! United? rates t atent 3,050,844 METHOD 9F MAKING END CAPS FOR PEPE RAILINGS Adolph A. Wagner, Milwaukee, Wis, assigner to R & B Wagner, inc, Milwaukee, Wis, a corporation of Wise cousin Original application Sept. 5, 1957, Ser. No. 682,215, new latent No. 2,917,!984, dated Dec. 15, 1959. Divided and this application Sept. 14}, 1959, er. No. 339,130 3 Gaines. (Cl. 29-520) This invention relates to improvements in a method of making end caps for pipe railings.

This application is a division of my copending application Serial No. 682,213, filed September 5, 1957, now Patent No. 2,917,084.

Heretofore it has been conventional in the art to weld end caps to close the otherwise open ends of railing pipes. The device of the present invention eliminates the need for welding, the novel fabricated end cap herein disclosed being readily secured to the open end of a railing pipe with a press fit. The absence of a weld improves the appearance of the railing.

My novel end cap consists of mating concentric hemispherical portions having tangentially extending coax al sleeve portions. The inner sleeve portion is longer than the outer sleeve portion and is telescopically received as a dowel within the pipe railing to connect the cap to the pipe. The outer sleeve portion has its end oifset from the end of the inner sleeve portion to provide a shoulder which abuts against the end of the pipe and defines the interconnected position thereof. The cap thus has a double wall in the area where the rail is most exposed to injury.

My method of fabricating the end cap is believed to be novel. Both inner and outer cap portions are desirably formed from substantially identical discs or annular blanks. The first blank is formed over a mandrel and the second blank is formed over the first blank without removing it from the mandrel.

Other objects, features and advantages of the invention will appear from the following disclosure in which:

FIG. 1 is a side elevation, partly in section, of a stairway and pipe railing to which the claimed end cap is applied.

FIG. 2 is an enlarged fragmentary cross section taken through an end cap as applied to an open ended railing pipe.

FIG. 3 is a fragmentary axial cross section taken through a die set in the final step of forming the end cap.

FIG. 4 is a perspective view of an end cap fabricated according to the present invention.

FIG. 5 is a cross section taken through a die set at an intermediate stage in the formation of the inner cap memher.

A conventional pipe railing may consist of uprights 1t and cross pipes 11, 12. Pipe 12 may be extended beyond upright 10, as shown at 13 and in ordinary course will have an open end. In the device of the present invention, the open end is closed by my novel end cap which consists of an inner member 14 and an outer member 15. The respective members 14, 15 comprise concentric hemispherical portions 16, 17 and tangentially extending coaxial sleeve portions 18, 19. Sleeve 18 has greater axial extent than sleeve 19 and functions as a dowel telescopically gesta t Patented Aug. 28, 1962 ice received within the open end of the pipe 13. The end of sleeve 19 acts as a shoulder to define the seated position of the cap therein.

Both members 14, 15 of the composite end cap are desirably fabricated from annular discs substantially identical in size and configuration. The inner member 14 is formed about mandrel 23 Whereafter outer member 15 is formed about inner member 14 which still retains the mandrel. The die 24 has a cavity 25, the radius of which is slightly smaller than the radius of preformed member 14 plus the thickness of member 15.

Inner member 14 is formed with an annular external groove 28, somewhat exaggerated in the drawings. In the course of closing the die 24 as shown in FIG. 3, the pressure of the slightly undersized die 24 rolls or flows the metal of outer cap member 15 into the groove 28 in the form of a rib 31 which engages with the groove 28 to interlock the members together.

The manner in which groove 28 is formed is suggested in FIG. 5. In forming the inner member 14, a die 53 engages the blank 22 to bend it at 34. FIG. 5 indicates a mid-point in the stroke of the die. Even after the die has completed its stroke to straighten out the blank to its tubular form 18, a residuum of the bend 34 remains as groove 23.

The outer annular edge of sleeve 18 is chamfered or beveled as shown at '32 to facilitate its enrty into the bore ing the end cap into the otherwise open end of pipe 13.

In seated position the parts are securely fastened and cannot be Withdrawn except with great difficulty.

The composite end cap fits very neatly on the end of the pipe railing and there is no Welding bead or the like to disfigure the joint. The double wall thickness of the cap is exceptionally sturdy to better absorb such impact shocks as may be imposed thereon.

I claim:

1. A method of forming a double walled cap of the character described and comprising the first step of forming an annular disc over a mandrel and into the shape of an inner member having a hemispherical end section and a tangential tubular extension, the second step of forming a second annular disc of substantially identical size and configuration with the first disc over the previously formed inner member to form an outer member having a hemispherical end section on a radius which is greater by an amount substantially equal to the thickness of the inner member, the end of the sleeve portion of the outer member being axially spaced from the end portion of the inner member, interlocking said inner and outer members before removal thereof from the mandrel and removing the interlocked members from the mandrel.

2. A method of forming a double walled cap of the character described and comprising forming an annular disc over a mandrel and into the shape of an inner memher having a hemispherical end section and a tangential tubular extension, forming an external groove on the tangential tubular extension of said inner member, forming a second annular disc of substantially identical size and configuration with the first disc over the previously formed inner member to form an outer member having a hemispherical end section on a radius which is greater by an amount substantially equal to the thickness of the inner inner member, forming an inner rib near the end of the sleeve portion of the outer member into said groove to interlock said inner and outer members, and removing 5 the interlocked members from the mandrel.

3. The method of claim 2 in which said discs are formed into said members by closing dies over said mandrel and between which said discs intervene, said groove being formed 'by the interaction of a first die with the disc for the'inner member and said rib being formed by the member.

References Cited in the file of this patent UNITED STATES PATENTS Grom et al AugLS, 1884 Schatz Apr. 19, 1910 V Alve'y June 1, 1915 Gmver, Sept. 17, 1918 Kuen Feb. 18, 1919 I Ranch Dec. 16, 1924 Serewicz Ian. 19, 1926 Dulmage Jan. 13, 1942 Warnkey ,Dec. 8, 1959 

